Puppet-valve for internal-combustion engines.



APPLICATION FILED OCT. I6, 1916.

Patented Aug. 14, 1917.

gnumuoz affoxnnq UNITED STATES PATENT OFFICE.

FRANK D. SHEPHERD, OF SALT LAKE CITY, UTAH.

PUPPET-VALVE FOR INTERNAL-COMBUSTION ENGINES.

To all whom it may concern:

Be it known that I, FRANK D. SHEPHERD, a citizen of the United States,and resident of Salt Lake City, in the county of Salt Lake, and in theState of Utah, have invented a certain new and useful Improvement inPuppet-Valves for Internal-Combustion Engines, and do hereby declarethat the following is a full, clear, and exact description thereof.

My invention relates to puppet valves, and my object is to provideaconstruction especially suited for internal combustion engines byreason of its characteristics of ready accessibility for cleaning andgrinding, freedom from liability to warp and break, and which will openand close at the right time, and when shut will be tight and remainshutuntil it is opened. The object of my invention, therefore, is toprovide a valve having these desirable and important characteristics andthey are attained by the means hereinafter specified and claimed.

In the accompanying drawings I illustrate several forms, or embodimentsof my invention, in which drawings- Figure l is a vertical sectionthrough an internal combustion engine having one form of my valve;

Fig. 2 is a similar view, but showing only the valve mechanism, andimmediately adjacent parts, illustrating a diiferent form of myinvention;

Fig. 3 is a like view to Fig. 2, showing still another form of myinvention;

Fig. 4 is a like view showing yet another construction embodying myinvention.

Giving a detailed description of the con struction shown in thedrawings, the engine cylinder 10 shown is of a type having the head 11cast integral therewith, and in said head is provided an internallythreaded opening 12, which leads from the outer end of the head into theport 13 controlled by the valve mechanism. Screwed in said hole 12, isan inverted cup shape casing 14, that isto say, it has the form of acylindrical shell with its outer end closed and its inner end open, andslidably fitting within said casing is the cylinder puppet valve 15,which cooperates with a seat 16 at the bottom of the port 13. Saidpuppet valve 15 is hollowed, or chambered with its lower end closed andits upper end open. The closed lower end forms a head 17 for engagementSpecification of Letters Patent.

Patented Aug. 14, 1917.

Application filed October 16, 1916. Serial No. 125,792.

with one end of a coil spring 18 placed W1th1n the valve whose upper endbears against the closed head, or upper end of the casing 14, andthusthe'valve is yieldingly held to its seat untilit is lifted by theaction of the usual cam 19 whose movement is transmitted through thevalve stem 20 through a slidable plunger 21 interposed between the camand the end of the valve stem. The valve stem may be integral with thevalve, as shown in Figs. 2 and 4, or separate therefrom, as shown inFig. 3. The valve stem, as shown clearly in Fig. 1, passes through anelongated guide 22 and is thereby restrained from lateral movement, asis also the valve when the valve stem and valve are joined.

The chambers that are due to the hollow form of the valve to accommodatethe spring and to the casing to accommodate the spring and allow forplay of the valve, are diminished in volume by placing therein withinthe-coils of the spring a filling device which may be attached either tothe valve, or-to the casing, or in part to each, said filling deviceoccupying as much space in the direction of movement of the valve, as ispossible without stopping, or restricting the play, or movement of thevalve necessary for the performance of its function in moving from itsseat to open the port 13. As shown in the drawings, said filling deviceis in the form of a cylindrical plug, which in Fig, 1 is a shell, ortube 23, with one end closed and which at its other end is threaded andscrewed into a threaded hole provided for the purpose in vthe valve head17. The upper closed end of said plug is polygonal on the outside forthe application of a wrench for turning it. As shown in Fig. 2, saidfilling device is in the form of a solid cylindrical plug 24 integralwith and projecting from the head of the casing 14; while as shown inFig. 3, it is a solid cylindrical plug 25 integral with the valve andextending upward therefrom. Besides being connected to either, or bothvalve and casing, said filling piece may be connected with neither, foras shown in Fig. 4, it may be a cylindrical plug 26, attached to a disk27 against which the upper end of the spring bears, and which itselfbears against the underside of the closed head of the casing 14.

By the employment of said filling device,

the unoccupied space within the valve and its casing is reduced to aminimum, and hence, should there be any leakage of gas by reason of aworn condition of that part of the valve which plays in and is guided bythe interior of the casing, the quantity finding its way into the valveand its casing would be so small as to be negligible.

If desired, one or more annular grooves 28 may be provided in theperiphery of the guide-forming extension of the valve for a lubricant,although practice has shown that lubrication is not indispensable.

It will be noted that there is no communication between the interior ofthe valve casing 14 and the external air, and this construction makesfor economy and eficiency of the engine.

As will be evident, especially since the closing of the valve iseffected by the expansive action of the spring, the closing of the valveis produced very positively, and

' the construction is simple by reason of the fewness of the parts, andit is strong since the parts are stout and compact. With the locationthat I give it, space that is otherwise not utilized in L-head andT-head engines, is utilized, there is an increase of power obtained fromthe engine and the parts are most readily accessible for removal forcleaning, or valve grinding. lhe matter of removal and replacement, isextremely simple since they involve merely the unscrewing and screwingof the casin 14. The valve closing spring acting expanslvely andpressing always in alinement with the longitudinal axis of the valve,there is no side pressure on the valve, such as is the case with valvesthat are closed by the pulling action of a spring which is connectedwith the valve stem, and which sidewise pressure causes wear on one sideof the valve guide and allows the entrance of air which renders the gasmixture too lean. It will be noted that the chamber in the valve 15 forthe accommodation of the coil spring is only deep enough to provide forthe roper accommodation of the spring, and, ence, that portion of thevalve situated in the port 13 and adjacent the seat is a member ofsubstantial thickness.

I show in the drawings but a sin 1e valve for the engine, but it, ofcourse, wi 1 be understood there are two valves, one for the intake andthe other for the exhaust. AL

though the engine shown is a water jacketed one, it is to be understoodmy valve mechanism is applicable to air cooled as well as water cooledengines, and its employment, of course, does not depend upon the numberof engine cylinders for it is applicable to one cylinder, or any numberof cylinders, and when more than one cylinder is used, whether they arecast separately, or en bloc.

For cooling the casing 14 it is formed mas er with annular heatradiating ribs, or fins 29; it has a fiat sided wrench-receiving head 30for convenient screwing and unscrewingof it; and in order to assure agas tight joint a gasket 31 is interposed between it and the enginehead.

It will be observed that the valve proper, or that part which cooperateswith the seat, is larger in diameter than the cylindrical guide-formingextension, and this large diameter is possible because of the provisionof the hole 12 for screwing the casing to the head, which hole 12 is ofample size and said valve proper need be of a diameter only suflicientlyless than that of the hole 12 toallow the passage of it through saidhole in assembling, or separating the parts.

When the filling plug has the tool-receiving head, as shown in Fig. 1, atool for grinding may be applied thereto; or as shown in Figs. 2, 3 and4, a slot 32 may be provided in the valve to receive the turning tool.

In constructing an engine embodying my invention, although the sparkplug 33 may be applied in any suitable place, I prefer to place it inthe center of the head of the cylinder, as shown in Fig. 1.

It will be evident from the various forms in which 1 illustrate myinvention as embodied, that such invention is not limited to any preciseconstruction and relative arrangement of the parts, and hence, it is tobe understood that 1 do not restrict myself even to such particularconstructions and relative arrangements of the parts as are shown in thedrawin s.

Having thus descri ed my invention what I claim is 1. The combination ofan engine cylinder having a valve-controlled passage with a single,stationary valve seat, a puppet valve having a guide-forming extensionand having a surface to cooperate with said single stationary seat, aguide connected with the c linder in a part surrounding said extensionand closed on all sides to the external atmosphere, said extension beinhollow to receive a spring, and a coil spring hearing at one end againstan internal surface on, said extension, and on .its other end against arelatively stationary part.

2. The combination of an engine cylinder having a valve-controlledpassage with a single, stationary valve seat, a puppet valve having aide-forming extenslon and having a sur ace to cooperate with said seat,a guide connected with the cylinder in a part surrounding said extensionon the side of the passage across from the valve seat, said extensionbeing hollow to receive a spring, a coil s ring hearing at one endagainst an inte'rna surface on said extension, and on its other endagainst a relatively stationary part, and a filling plug within saidcoil spring.

mas er 3. The combination of an engine cylinder having avalve-controlled passage with a single, stationary valve seat, a puppetvalve having a guide-forming extension, a guide casing having adetachable threaded connection with a hole in the cylinder wall closedon all sides to the external atmosphere, said extension beinghollow toreceive aispring, and a coil spring bearing at one end against aninterna surface on said extension, and on its other end against arelatively stationary art.

4. The combination of an engine cylinder havin an integral head andprovided at the end adjacent said head with a passage having a slngle,stationary valve seat, said head having in line with said valve seat aninternally threaded hole, a valve for said seat having on one side astem and on the other side a guide-forming extension, a cylindricalcasing having a threaded portion at one end that engages said threadedhole, and. having its other end closed and its side closed wherebycommunication with the external atmosphere is revented, and its interiorforming a gui e for said valve extension, and said valve extension beinghollow, a spring within said casing, and the chamber in the valveextension actin to push the valve to its seat, and a fi ing plug withinsaid coil spring;

5. The combination of an-engine cylinder having a valve-controlledpassage with a stationar valve seat, a puppet valve having a guideormingextension, a guide casing surrounding said extension and closed to theatmosphere on all sides beyond said extension, and said extension beinhollow to receive a spring, and an expansible acting coil spring hearingat one end against the valve,

and at the other end against the closed end of the casing.

6. The combination of an engine cylinder having a valve controlled passae with a stationary valve seat at one side of said passage, a puppetvalve having a surface to cooperate with said seat and reaching acrosssaid passage to the opposite side thereof, a guide casing closed to theexternal atmosphere having a chamber into which said puppet valvereaches, and a spring in said chamber hearing at its outer end against arelatively stationary surface and at its inner end against the portionof the valve extending into the casing chamber, whereby the spring isprotected from high temperature in said passage, the portion of thevalve situated in said uide casing being hollow and surrounding t espring.

7. The combination of an engine cylinder having a valve controlledpassage with a stationary valve seat at one side of said passage, a pupet valve having a surface to cooperate w1t said seat and reaching acrosssaid passage to the opposite side thereof,-a guide casing closed totheexternal atmosphere having a chamber into which said puppet valvereaches, and a spring in said chamber bearing at its outer end againsta. relatively stationary" surface and at its inner end against theportion of the valve extend-- ing into the casing chamber, whereby thespring is protected from high temperature in said passage, the portionof the valve situat-ed in said uide casing being hollow and surroundingt e spring, and a filling plug within said coil spring.

In testimony that I claim the foregoing I have hereuntoset my hand.

FRANK D. SHEPHERD.

